JP6805660B2 - Airless tire - Google Patents

Description

The present invention relates to an airless tire that has both wet performance and steering stability performance and can improve noise performance.

In recent years, various airless tires have been proposed. Airless tires can support the load by their own structural members without using high pressure air. Therefore, the airless tire has an advantage that it does not puncture.

For example, Patent Document 1 below describes an airless tire composed of an annular spoke structure and a tread ring on the outer periphery thereof. This spoke structure is divided into left and right in the tire width direction, and the spokes of both divided bodies are shifted by half a pitch to reduce the variation in tire rigidity in the circumferential direction and improve steering stability performance. ..

Japanese Unexamined Patent Publication No. 2008-162495

In Patent Document 1, the tread ring is formed as one annular body, and a groove for improving wet performance is formed in the tread ring. In the airless tire of Patent Document 1, a groove continuous in the circumferential direction is formed to improve wet performance, but such a circumferential groove forms a tubular space with the road surface and is generated there. There is a problem that the noise performance is lowered due to the road noise.

The present invention has been devised in view of the above circumstances, and is based on providing a gap for drainage between tread rings adjacent in the tire axial direction, and achieves both wet performance and steering stability performance. At the same time, the main purpose is to provide airless tires that can improve noise performance.

The present invention is an airless tire in which at least three airless tire pieces are arranged side by side in the tire axial direction, and each airless tire piece includes a cylindrical tread ring having a ground contact surface, and the tread. The ring has a width W1 in the tire axial direction that is substantially constant in the tire circumferential direction, and a gap for drainage having a width W5 in the tire axial direction is provided between the tread rings adjacent to the tire axial direction. The width W1 of each tread ring is 15 mm or more, and the width W5 of each gap is 3 mm or more.

In the airless tire according to the present invention, the width W5 of the gap is preferably 10% to 25% of the width W1 of the tread ring forming the gap.

In the airless tire according to the present invention, the total width W of the tread in the tire axial direction is 51 to 125 mm, the tire is composed of three or four airless tire pieces, and the width W1 of each tread ring is 15 to 40 mm. The width W5 of each of the gaps is preferably 3 to 8 mm.

In the airless tire according to the present invention, the total width W of the tread in the tire axial direction is 126 to 265 mm, the tire is composed of 4 to 6 airless tire pieces, and the width W1 of each tread ring is 20 to 60 mm. The width W5 of each of the gaps is preferably 4 to 12 mm.

In the airless tire according to the present invention, the total width W of the tread in the tire axial direction is 266 to 455 mm, the tire is composed of 5 to 8 airless tire pieces, and the width W1 of each tread ring is 30 to 80 mm. The width W5 of each of the gaps is preferably 6 to 16 mm.

In the airless tire according to the present invention, each of the airless tire pieces includes a rim arranged inside the tread ring in the tire radial direction, and a substantially constant tire axial width is provided between the rims adjacent to the tire axial direction. It is desirable that an inner gap having W6 is provided.

In the airless tire according to the present invention, it is desirable that the width W6 of the inner gap is equal to the width W5 of the gap located on the outer side in the radial direction of the tire.

In the airless tire of the present invention, at least three airless tire pieces are arranged side by side in the tire axial direction. In such an airless tire, the total tread width of the airless tire can be adjusted by changing the number and width of the plurality of airless tire pieces. As such an airless tire piece, a common airless tire piece can be used for airless tires of different sizes, and the sharing of parts can be promoted.

In the airless tire of the present invention, each airless tire piece includes a cylindrical tread ring having a ground contact surface, and the tread ring has a width W1 in the tire axial direction substantially constant in the tire circumferential direction and is in the tire axial direction. A gap for drainage having a width W2 in the tire axial direction is provided between the adjacent tread rings. Since such an airless tire does not form a tubular space with the road surface and can reduce road noise, the noise performance of the airless tire can be improved. Further, since a gap for drainage is provided between the tread rings, the wet performance of the airless tire can be improved.

Further, in the airless tire of the present invention, the width W1 of each tread ring is 15 mm or more, and the width W2 of each gap is 3 mm or more. Such an airless tire has high rigidity and a gap required for drainage, and can achieve both wet performance and steering stability performance in a well-balanced manner.

It is an overall perspective view (partially broken view) which shows one Embodiment of the airless tire of this invention. It is a perspective view (partially broken view) of an airless tire piece. It is a cross-sectional view of the meridian of an airless tire piece. It is a cross-sectional view of the meridian of an airless tire. It is an overall perspective view of the airless tire of another embodiment. It is an overall perspective view of the airless tire of still another embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an overall perspective view showing the airless tire 1 of the present embodiment. As shown in FIG. 1, in the airless tire 1 of the present embodiment, at least three airless tire pieces 2 are arranged side by side in the tire axial direction. In this embodiment, an airless tire 1 in which three airless tire pieces 2 are arranged is exemplified.

FIG. 2 is a perspective view of each airless tire piece 2. As shown in FIG. 2, the airless tire piece 2 of the present embodiment includes a cylindrical tread ring 3 having a ground contact surface 3a and a wheel 4 arranged inside the tread ring 3 in the radial direction of the tire. .. The tread ring 3 is formed of, for example, an elastic body such as rubber. A reinforcing body (not shown) such as a steel cord may be embedded in the tread ring 3.

FIG. 3 is a cross-sectional view of the meridian of the airless tire piece 2. As shown in FIGS. 2 and 3, the tread ring 3 of the airless tire piece 2 of the present embodiment has a width W1 in the tire axial direction and a thickness t1 in the tire radial direction that are substantially constant in the tire circumferential direction. ing. The width W1 of the tread ring 3 is preferably 15 mm or more. If the width W1 of the tread ring 3 is smaller than 15 mm, the rigidity of the tread ring 3 is lowered, and the steering stability performance of the airless tire 1 may be significantly lowered.

The thickness t1 of the tread ring 3 is preferably 30% to 120% of the width W1 of the tread ring 3. Such a tread ring 3 can achieve both appropriate rigidity and elasticity, can improve the steering stability performance of the airless tire 1, and can improve the riding comfort performance.

It is desirable that the ground contact surface 3a of the tread ring 3 is a plain rib in which a groove or the like is not formed. Such a tread ring 3 has high rigidity and can improve the steering stability performance of the airless tire 1. The tread ring 3 may be formed with through holes (not shown) or the like as long as the rigidity of the tread ring 3 is not significantly affected.

The wheel 4 of the present embodiment has a cylindrical rim 5 arranged adjacent to the tread ring 3, a cylindrical hub ring 6 arranged inside the rim 5 in the radial direction of the tire, and the rim 5 and the hub ring 6. It includes a plurality of spokes 7 to be connected. The wheel 4 has a rim 5, a hub ring 6, and spokes 7 integrally molded from a polymer material such as polyurethane.

The rim 5 has a width W2 in the tire axial direction that is substantially constant in the tire circumferential direction. It is desirable that the width W2 of the rim 5 is substantially equal to the width W1 of the tread ring 3. It is desirable that the rim 5 is firmly fixed to the tread ring 3. As a means for fixing the rim 5 and the tread ring 3, for example, a means for arranging a preformed tread ring 3 in a mold and integrally molding the wheel 4 including the rim 5 can be adopted.

It is desirable that the hub ring 6 is fixed to the axle (not shown) via a hub portion (not shown) formed of a metal material. The hub ring 6 has side surfaces 6a that come into contact with each other when the airless tire pieces 2 are arranged side by side in the tire axial direction. The hub ring 6 has a width W3 in the tire axial direction that is substantially constant in the tire circumferential direction. The width W3 of the hub ring 6 of the present embodiment is larger than the width W1 of the tread ring 3.

Each spoke 7 has, for example, a plate shape, and is provided in plurality in the tire circumferential direction. The spokes 7 of the present embodiment are substantially rectangular and have a substantially constant width W4 in the tire axial direction. It is desirable that the width W4 of the spokes 7 is substantially equal to the width W1 of the tread ring 3. The spokes 7 may have a substantially trapezoidal shape in which the connecting side with the hub ring 6 is equal to the width W3 of the hub ring 6. As for the shape of the spoke 7, various well-known modes may be adopted in addition to these modes.

As shown in FIG. 1, as the airless tire piece 2, an airless tire piece 2 having an arbitrary size can be selected from a plurality of airless tire pieces 2 having different widths W1 to W4 (shown in FIG. 3). In the airless tire 1 of the present embodiment, two first airless tire pieces 2A and one second airless tire piece 2B are arranged side by side in the tire axial direction.

In such an airless tire 1, by changing the number N of the plurality of airless tire pieces 2 and the widths W1 to W4 (shown in FIG. 3), the total tread width W in the tire axial direction of the airless tire 1 (shown in FIG. 4). ) Can be adjusted. As such an airless tire piece 2, the same airless tire piece 2 can be used for the airless tires 1 having different sizes, and the sharing of parts can be promoted.

Here, the total tread width W of the airless tire 1 is the length from the tread end on one side of the airless tire piece 2 located on the most one side to the tread end on the other side of the airless tire piece 2 located on the other side. Is.

In the present embodiment, the hub rings 6 of each airless tire piece 2 are fixed in contact with each other. The fixing of each airless tire piece 2 may be performed when fixing to the hub portion (not shown), or may be performed before fixing to the hub portion. Well-known fixing means (not shown) such as bolt fastening may be appropriately adopted for fixing each airless tire piece 2.

In the present embodiment, the spokes 7 of each airless tire piece 2 are arranged so as to be at the same position in the tire circumferential direction. The spokes 7 of each airless tire piece 2 may be arranged so as to be displaced from each other in the tire circumferential direction.

The airless tire 1 of the present embodiment is provided with a drainage gap 8 between the tread rings 3 of the airless tire pieces 2 adjacent to each other in the tire axial direction. Such a gap 8 can remove water on the road surface when traveling on a wet road surface, and can improve the drainage property of the airless tire 1. Further, since the gap 8 is open on the inner side in the radial direction of the tire, the road noise of the airless tire 1 can be reduced without forming a tubular space with the road surface.

FIG. 4 is a cross-sectional view of the meridian of the airless tire 1. As shown in FIG. 4, the gap 8 has a substantially constant width W5 in the tire axial direction. The width W5 of each gap 8 is preferably 3 mm or more. If the width W5 of the gap 8 is smaller than 3 mm, water on the road surface cannot be removed, and the wet performance of the airless tire 1 may not be improved so much.

The width W5 of each gap 8 is preferably 10% to 25% of the width W1 of the tread ring 3 forming the gap 8. Here, the width W5 of the gap 8 is substantially equal to the difference (W3-W1) between the width W3 of the hub ring 6 and the width W1 of the tread ring 3. Therefore, the difference (W3-W1) between the width W3 of the hub ring 6 and the width W1 of the tread ring 3 is 10% to 25% of the width W1 of the tread ring 3. Such an airless tire 1 has high rigidity and a gap 8 required for drainage, and can achieve both wet performance and steering stability performance in a well-balanced manner.

The airless tire 1 of the present embodiment is composed of a first airless tire piece 2A and a second airless tire piece 2B having different widths W1 of the tread ring 3. In the present embodiment, the airless tire 1 in which the width W1A of the first tread ring 3A of the first airless tire piece 2A is larger than the width W1B of the second tread ring 3B of the second airless tire piece 2B is exemplified. Each airless tire piece 2 may be the same one having the same width W1.

The width W5 of the gap 8 between the first airless tire piece 2A and the second airless tire piece 2B is 10% to 25% of the average value of the width W1A of the first tread ring 3A and the width W1B of the second tread ring 3B. It is preferably%. Further, the width W5 of the gap 8 is the difference (W3A-W1A) between the width W3A of the first hub ring 6A of the first airless tire piece 2A and the width W1A of the first tread ring 3A and the first of the second airless tire piece 2B. It is equal to the average value of the difference (W3B-W1B) between the width W3B of the 2 hub ring 6B and the width W1B of the second tread ring 3B.

An inner gap 9 having a substantially constant tire axial width W6 is provided between the rims 5 of the airless tire pieces 2 adjacent to each other in the tire axial direction. It is desirable that the width W6 of the inner gap 9 is substantially equal to the width W5 of the gap 8 located on the outer side in the radial direction of the tire. Since such an inner gap 9 opens the entire inside of the gap 8 in the radial direction of the tire, the road noise of the airless tire 1 can be further reduced.

In the present invention, by changing the number N of the airless tire pieces 2 constituting the airless tire 1 and the sizes of the widths W1 to W6, the airless tire 1 having a different total tread width W in the tire axial direction can be configured. Hereinafter, the airless tires 1, 10 and 11 of different embodiments will be described with reference to the dimensions shown in FIG.

The airless tire 1 shown in FIG. 1 is, for example, an airless tire 1 having a tread total width W of 51 to 125 mm. It is desirable that the airless tire 1 of this embodiment is composed of three or four airless tire pieces 2. The width W1 of each tread ring 3 of each airless tire piece 2 is preferably 15 to 40 mm. The width W5 of each gap 8 is preferably 3 to 8 mm.

In the airless tire 1 having a tread total width W of 51 to 125 mm, the number N of the airless tire pieces 2 is set to 3 or 4, and each width W1 and W5 is defined in the above range, which is necessary for high rigidity and drainage. It has a large gap 8 and can achieve both wet performance and steering stability performance in a well-balanced manner.

FIG. 5 is an overall perspective view of the airless tire 10 of another embodiment. The airless tire 10 shown in FIG. 5 is, for example, an airless tire 10 having a tread total width W of 126 to 265 mm. It is desirable that the airless tire 10 of this embodiment is composed of 4 to 6 airless tire pieces 2. The width W1 of each tread ring 3 of each airless tire piece 2 is preferably 20 to 60 mm. The width W5 of each gap 8 is preferably 4 to 12 mm.

In the airless tire 10 having a tread total width W of 126 to 265 mm, the number N of the airless tire pieces 2 is set to 4 to 6, and each width W1 and W5 are defined in the above range, which is necessary for high rigidity and drainage. It has a gap of 8 and can achieve both wet performance and steering stability performance in a well-balanced manner.

FIG. 6 is an overall perspective view of the airless tire 11 of still another embodiment. The airless tire 11 shown in FIG. 6 is, for example, an airless tire 11 having a tread total width W of 266 to 455 mm. It is desirable that the airless tire 11 of this embodiment is composed of 5 to 8 airless tire pieces 2. The width W1 of each tread ring 3 of each airless tire piece 2 is preferably 30 to 80 mm. The width W5 of each gap 8 is preferably 6 to 16 mm.

In the airless tire 11 having a tread total width W of 266 to 455 mm, the number N of the airless tire pieces 2 is set to 5 to 8, and each width W1 and W5 are defined in the above range, which is necessary for high rigidity and drainage. It has a gap of 8 and can achieve both wet performance and steering stability performance in a well-balanced manner.

Although the particularly preferable embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments and can be modified into various embodiments.

Airless tires (tread overall width 195 mm, outer diameter 635 mm) as shown in FIGS. 1 to 6 were prototyped based on the specifications shown in Table 1. Wet performance, steering stability performance and noise performance were tested using these test tires. The test method is as follows.

<Wet performance>
Each test tire was set on the inside drum tester and adjusted to a wet state with a water film of 5 mm. A vertical load of 4.0 kN was applied to the test tire, and a speed at which the maximum cornering force was halved was measured with a side slip angle of 1 degree. The result is an index with Comparative Example 1 as 100, and the larger the value, the better the wet performance.

<Stable steering performance>
Each test tire was set in the inside drum tester in a dry state. A vertical load of 4.0 kN was applied to the test tire, and a speed at which the maximum cornering force was halved was measured with a side slip angle of 1 degree. The result is an index with Comparative Example 1 as 100, and the larger the value, the better the steering stability performance.

<Noise performance>
In the anechoic chamber, each test tire was set on the drum tester. A sound pressure level of 800 to 1000 Hz was measured by a measuring machine when a vertical load of 4.0 kN was applied to the test tire and the tire was run at a speed of 100 km / h. The result is an index with Comparative Example 1 as 100, and the larger the value, the better the noise performance.

The test results are shown in Table 1.

As is clear from Table 1, it was confirmed that the airless tires of the examples significantly improved the wet performance and the noise performance while suppressing the deterioration of the steering stability performance as compared with the comparative example.

1 Airless tire 2 Airless tire piece 3 Tread ring 8 Gap

Claims (7)

Airless tires
At least three airless tire pieces are arranged side by side in the tire axial direction.
Each airless tire piece includes a cylindrical tread ring having a tread surface and wheels arranged inside the tread ring in the radial direction of the tire .
The tread ring has a width W1 in the tire axial direction that is substantially constant in the tire circumferential direction.
A gap for drainage having a substantially constant width W5 in the tire axial direction is provided between the tread rings adjacent to the tire axial direction.
The width W1 of each of the tread rings is 15 mm or more.
The width W5 of each gap state, and are more 3 mm,
The wheel includes a cylindrical rim arranged adjacent to the tread ring, a cylindrical hub ring arranged inside the tire radial direction of the rim, and a plurality of spokes connecting the rim and the hub ring. Airless tires characterized by including .
The airless tire according to claim 1, wherein the width W5 of the gap is 10% to 25% of the width W1 of the tread ring forming the gap. The total width W of the tread in the tire axial direction is 51 to 125 mm.
Consists of 3 or 4 of the airless tire pieces
The width W1 of each of the tread rings is 15 to 40 mm.
The airless tire according to claim 1 or 2, wherein the width W5 of each gap is 3 to 8 mm. The total width W of the tread in the tire axial direction is 126 to 265 mm.
Consists of 4 to 6 airless tire pieces
The width W1 of each of the tread rings is 20 to 60 mm.
The airless tire according to claim 1 or 2, wherein the width W5 of each gap is 4 to 12 mm. The total width W of the tread in the tire axial direction is 266 to 455 mm.
Consists of 5 to 8 airless tire pieces
The width W1 of each of the tread rings is 30 to 80 mm.
The airless tire according to claim 1 or 2, wherein the width W5 of each gap is 6 to 16 mm. Wherein the inter-rim, airless tire according to any one of claims 1 to 5 the inner gap is provided having a substantially constant in the tire axial width W6 adjacent to tire axial direction. The airless tire according to claim 6, wherein the width W6 of the inner gap is equal to the width W5 of the gap located on the outer side in the radial direction of the tire.

Images